it's a complex situation of time, your genes which you can't change and your environment. you can thing about brain diseases as really a disorder of a lifetime. there are things we can do. we can stamen tally active physically fit, socially engaged, eat a heart-healthy diet. >> we do all those things. what else? >> we can avoid head injuries, we can protect ourselves, have good positive lifestyles, no smokes, drinking drug use. i think more importantly is when we find we have a problem go to medical attention really early because one of the biggest risk factors is diabetes and things. >> physiologically was there something? you said less atrophy. what about size? >> the size for 280-year-old looks like the 50-year-old brains and the pew people who had died they study under autopsy, they seemed to have more neurons, more brain cells in certain regions of the brain that are responsible for the higher order of processing. >> in the future do, you think there will be something you can do that will change things? is there a miracle drug? >> if we know why they're staying so rob